13 research outputs found
Aedes albopictus salivary proteins adenosine deaminase and 34k2 interact with human mast cell specific proteases tryptase and chymase
When mosquitoes probe to feed blood, they inoculate a mixture of salivary molecules into vertebrate hosts' skin causing acute inflammatory reactions where mast cell-derived mediators are involved. Mosquito saliva contains many proteins with largely unknown biological functions. Here, two Aedes albopictus salivary proteins - adenosine deaminase (alADA) and al34k2 - were investigated for their immunological impact on mast cells and two mast cell-specific proteases, the tryptase and the chymase. Mouse bone marrow-derived mast cells were challenged with increased concentrations of recombinant alADA or al34k2 for 1, 3, and 6 h, and to measure mast cell activation, the activity levels of beta-hexosaminidase and tryptase and secretion of IL-6 were evaluated. In addition, a direct interaction between alADA or al34k2 with tryptase or chymase was investigated. Results show that bone marrow-derived mast cells challenged with 10 mu g/ml of alADA secreted significant levels of beta-hexosaminidase, tryptase, and IL-6. Furthermore, both al34k2 and alADA are cut by human tryptase and chymase. Interestingly, al34k2 dose-dependently enhance enzymatic activity of both tryptase and chymase. In contrast, while alADA enhances the enzymatic activity of tryptase, chymase activity was inhibited. Our finding suggests that alADA and al34k2 via interaction with mast cell-specific proteases tryptase and chymase modulate mast cell-driven immune response in the local skin microenvironment. alADA- and al34k2-mediated modulation of tryptase and chymase may also recruit more inflammatory cells and induce vascular leakage, which may contribute to the inflammatory responses at the mosquito bite site
Proof of the Equivalence Theorem in the Chiral Lagrangian Formalism
A general proof of the equivalence theorem in electroweak theories with the
symmetry breaking sector described by the chiral Lagrangian is given in the
gauge by means of the Ward-Takahashi identities. The precise form of
the theorem contains a modification factor associated with each
external Goldstone boson similar to that in the standard model. is
exactly unity in our previously proposed renormalization scheme, {\it
Scheme-II}.Comment: 10 pages, A few words have been added below eq.(22) to make our
meaning more precis
RNA N6-methyladenosine-modified-binding protein YTHDF1 promotes prostate cancer progression by regulating androgen function-related gene TRIM68
Abstract Purpose There is no report about the direct relationship between m6A modification and androgen receptor (AR)-related genes in prostate cancer (PC). We aimed to study the mechanisms of m6A methylation in regulating the pathogenesis of PC from the perspective of AR-related genes. Methods qRT-PCR was applied to detect the expression of m6A-related genes in PC cell with or without AR inhibitor. The effects of YTHDF1 knockdown on PC cell viability, apoptosis, migration and invasion were investigated using flow cytometry, wound healing and transwell assays, respectively. The mechanism of YTHDF1 action was investigated using m6A RNA immunoprecipitation (MeRIP) sequencing. The biological functions of YTHDF1 were also explored through in vivo experiments. Results YTHDF1 was significantly down-regulated in AR inhibitor group. YTHDF1 knockdown significantly decreased AR level, viability and m6A methylation level of PC cells. TRIM68 was identified as a direct target of YTHDF1. Both YTHDF1 and TRIM68 knockdown increased apoptosis, and decreased cell viability, migration, and invasion of PC cells, while TRIM68 overexpression reversed the effects of YTHDF1 knockdown on PC cells. In addition, knockdown of YTHDF1 or TRIM68 significantly decreased the m6A methylation level, and mRNA and protein levels of YTHDF1, TRIM68 and AR in PC cells, while TRIM68 overexpression increased the expression levels above. Furthermore, subcutaneous xenografts of nude mice also revealed that TRIM68 could reverse the effects of YTHDF1 knockdown in PC in vivo. Conclusion This study suggested the key role of YTHDF1-mediated m6A modification in PC progression by regulating androgen function-related gene TRIM68 in PC
Aedes albopictus salivary adenosine deaminase is an immunomodulatory factor facilitating dengue virus replication
Abstract The Asian tiger mosquito, Aedes albopictus, is an important vector for the transmission of arboviruses such as dengue virus (DENV). Adenosine deaminase (ADA) is a well-characterized metabolic enzyme involved in facilitating blood feeding and (or) arbovirus transmission in some hematophagous insect species. We previously reported the immunologic function of ADA by investigating its effect on mast cell activation and the interaction with mast cell tryptase and chymase. The 2-D gel electrophoresis and mass spectrometry analysis in the current study revealed that ADA is present and upregulated following mosquito blood feeding, as confirmed by qRT-PCR and western blot. In addition, the recombinant ADA efficiently converted adenosine to inosine. Challenging the Raw264.7 and THP-1 cells with recombinant ADA resulted in the upregulation of IL-1β, IL-6, TNF-α, CCL2, IFN-β, and ISG15. The current study further identified recombinant ADA as a positive regulator in NF-κB signaling targeting TAK1. It was also found that recombinant Ae. albopictus ADA facilitates the replication of DENV-2. Compared with cells infected by DENV-2 alone, the co-incubation of recombinant ADA with DENV-2 substantially increased IL-1β, IL-6, TNF-α, and CCL2 gene transcripts in Raw264.7 and THP-1 cells. However, the expression of IFN-β and ISG15 were markedly downregulated in Raw264.7 cells but upregulated in THP-1 cells. These findings suggest that the immunomodulatory protein, Ae. albopictus ADA is involved in mosquito blood feeding and may modulate DENV transmission via macrophage or monocyte-driven immune response